提昇衝擊擴散火焰燃燒效率與節能機制之探討

The mechanism for improving jet impingment diffusion flame combustion efficiency and reducing fuel consumption.

謝明濬(Ming-Jui Hsieh)

指導教授 ： 蘇艾

元智大學/工程學院/機械工程學系/碩士(2005年)

摘要

本實驗主要在研究相向噴流衝擊火焰燃燒結構，藉由控制燃料流量和氮氣與甲烷體積比來觀察火焰結構變化。運用燃氣間對衝所造成停滯面做為火焰的助燃機構，燃燒效率及昇溫能力均優於傳統擴散火焰好，並且可短化火焰長度。近似預混火焰燃燒中火焰燃燒較好，燃料的燃燒結果亦完全，減少燃料不完全燃燒而產生的碳粒子。隨著氮氣與甲烷體積比的增加，火焰長度會縮短，火焰藍色預混貧油區比例增加，並且火焰內部溫度分布較為均勻，由火焰平面圖及EXCEL軟體計算分析後，當N2 /（CH4+N2)混合比在30％時，火焰燃燒場平均溫度、高溫區及火焰結構的穩定性為所有混合比中最佳。

關鍵字

相向噴流衝擊擴散火焰 ； 近似預混火焰燃燒 ； 燃燒效率

並列摘要

The structures of a jet impinging flame under different Renolds numbers and fuel dilution are observed. Through construction of impinging flame of methane fuel at the stagnation plane, and control of the ratio of nitrogen to methane in their mixture, it is observed that the combustion length decreases and combustion efficiency increases, and that the temperature distribution of flame is uniform. It is concluded from flame diagrams and EXCEL analysis that the average temperature, high-temperature region, and stability of a flame are optimized with a N2 to (CH4+N2) ratio of 30%.

並列關鍵字

impinging flame ； combustion efficiency

參考文獻

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